INRIM Sr Optical Clock: An Optically Loaded Apparatus for High-Stability Metrology

We report on the development of a new compact strontium optical lattice clock employing a 2D-MOT as cold atomic source. The clock system reliability is currently studied using the most abundant isotope, the bosonic
⁸⁸
Sr. More than 10
⁵
88Sr atoms are loaded in the optical lattice at 813 nm at temperatures of few microKelvin. All the needed optical frequencies are stabilized to a zero-CTE high finesse optical resonator, and can be operated without frequency adjustments for weeks. The system shows the advantage of optical guiding and switching the atomic source to the clock spectroscopy region by demonstrating more than 17 s lifetime. First spectroscopy tests on the clock transition on
⁸⁸
Sr atoms has been performed by magnetic-field induced spectroscopy.